<template>
  <div class="sidebar">
    <el-menu
      class="sidebar-el-menu"
      :default-active="onRoutes"
      :collapse="collapse"
      background-color="#324157"
      text-color="#bfcbd9"
      active-text-color="#20a0ff"
      unique-opened
      router
    >
      <template v-for="item in routes">
        <template v-if="item.subs">
          <el-submenu :index="item.path" :key="item.path">
            <template slot="title">
              <i :class="item.icon"></i>
              <span slot="title">{{ item.meta.title }}</span>
            </template>
            <template v-for="subItem in item.subs">
              <el-submenu v-if="subItem.subs" :index="subItem.index" :key="subItem.index">
                <template slot="title">{{ subItem.title }}</template>
                <el-menu-item v-for="(threeItem, i) in subItem.subs" :key="i" :index="threeItem.index">{{ threeItem.title }}</el-menu-item>
              </el-submenu>
              <el-menu-item v-else :index="subItem.index" :key="subItem.index">{{ subItem.title }}</el-menu-item>
            </template>
          </el-submenu>
        </template>
        <template v-else>
          <el-menu-item :index="item.redirect || item.path" :key="item.path">
            <i :class="item.meta.icon"></i>
            <span slot="title">{{ item.meta.title }}</span>
          </el-menu-item>
        </template>
      </template>
    </el-menu>
  </div>
</template>

<script>
import bus from '@/utils/bus'
import { routes } from '@/router'
const src = routes[1].children
export default {
  data() {
    return {
      collapse: false,
      routes: src.filter(({ meta }) => {
        if (!meta) return
        if (!meta.title) return
        if (meta.power) return
        return true
      }),
    }
  },
  computed: {
    onRoutes() {
      return this.$route.path.replace('/', '')
    },
  },
  created() {
    // 通过 Event Bus 进行组件间通信，来折叠侧边栏
    bus.$on('collapse', (msg) => {
      this.collapse = msg
      bus.$emit('collapse-content', msg)
    })
    bus.$on('setUser', (user) => {
      this.routes = src.filter(({ meta }) => {
        if (!meta) return
        if (!meta.title) return
        if (meta.power) {
          if (!user.power.includes('menu.' + meta.power)) return
        }
        return true
      })
    })
  },
}
</script>

<style scoped>
.sidebar {
  display: block;
  position: absolute;
  left: 0;
  top: 70px;
  bottom: 0;
  overflow-y: scroll;
}
.sidebar::-webkit-scrollbar {
  width: 0;
}
.sidebar-el-menu:not(.el-menu--collapse) {
  width: 250px;
}
.sidebar > ul {
  height: 100%;
}
</style>
